Peeter Cornet (Pierre, Pietro, Peter, Pieter) (ca. 1570-80 – 27 March 1633) was a Flemish composer and organist of the early Baroque period. Although few of his compositions survive, he is widely considered one of the best keyboard composers of the early 17th century.

Very little is known about Cornet's life. Much of the information comes from a letter by his widow. Cornet was born in Brussels, which was then the capital of Southern Netherlands, in the 1570s. The family included numerous musicians, among them a violinist, singers and organists. From 1603 to 1606 Cornet worked as organist at Saint Nicholas Church, Brussels; around 1606 he became court organist to Albert VII, Archduke of Austria and his wife Infanta Isabella Clara Eugenia of Spain, also in Brussels. For one month, in March 1611, Cornet was a canon at Soignies, but he gave up his canonry to marry.

Cornet is listed as chapel organist in the surviving court account books from 1612–1618. His colleagues included important English composers Peter Philips (who acted as godfather to one of Cornet's children) and John Bull, as well as fellow Flemish composers Géry Ghersem and Matthijs Langhedul. Apparently Cornet was also active as an organ consultant and builder. In 1615 he provided advice concerning the organ of St. Rumbolds Cathedral (Sint-Romboutskathedraal) in Mechelen, and in 1624 he signed a contract to build a choir division for the same organ. (Source: Wikipedia)